Thread brake for spinning or twisting spindles



Jan. 20, 1970 w, HElMEs ET AL 3,490,221

THREAD BRAKE FOR SPINNING OR TWISTING SPINDLES Filed Feb. 17, 1969 3 Sheets-Sheet l FIG. 3

IMVE/VTOR s Jan. 20, 1970 w. HEIMES ET AL THREAD BRAKE FOR SPINNING OR TWISTING SPINDLES 3 Sheets-Sheet 2 Filed Feb. 17, 1969 y a E r II III. hill-III Jan. 20, 1970 w, HE|ME$ ETAL THREAD BRAKE FOR SPINNING OR TWISTING SFINDLES Filed Feb. 17, 1969 3 Sheets-Sheet 5 HI w FIG. 5

6224/0 Frn a a e 2? United States Patent 3,490,221 THREAD BRAKE FUR SPINNING OR TWISTING SPINDLES Willy Heimes, Krefeld, Gustav Franzen, Neersen, near Krefeld, and Klaus Nimtz, Krefeld, Germany, assignors to Palitex Project-Company GmbH, Krefeld, Germany Filed Feb. 17, 1969, Ser. No. 799,700 Claims priority, application Germany, Feb. 16, 1968,

Int. Cl. D011 1/1 0, 7/86, 13/04 U.S. Cl. 5758.86 11 Claims ABSTRACT OF THE DISCLOSURE A thread brake for spinning and twisting spindles in which the hollow spindle shank has arranged therein a thread brake comprising a brake member which is pivotable toward and away from the thread passing over an inclined surface within the brake housing.

Thread brakes for spinning or twisting spindles serve for braking the thread or threads unwinding from the delivery bobbin and circulating about the spindle axis, and also serve for compensating different thread tensions.

With most heretofore known spindles the thread brake comprises a brake housing mounted upon the hollow spindle shank or arranged in the hollow spindle shank. The thread or threads are axially passed through the brake housing while in said brake housing there is provided either a conical braking surface engaged, for instance, by a spring pressure biased ball or two braking surfaces are located opposite to each other which conically open toward and in opposite direction to the moving direction of the thread. Between the said braking surfaces there extends a braking punch with two semi-spherical ends. The braking punch consists of two cylindrical sleeves telescopically arranged one within the other and compressed against a spring pressure, or a one-piece braking punch is provided. With the last mentioned design, one of the conical braking surfaces is displaceable toward the other, for instance, against spring pressure. When the spring pressure is variable, for instance by exchanging the employed spring for another one, the semi-spherical ends of the braking punch are adapted to exert against the braking surfaces such a pressure as is required by the respective threads passing therethrough.

Another heretofore known thread brake for spinning or twisting spindles comprises two braking bodies having parallelly extending braking surfaces engaging each other. Of these braking bodies one is rotatable about an axis perpendicular to the longitudinal extension of said braking body and is held against a spring pressure on a pivotal lever arm in such a way that one braking surface is under the influence of the thread passing through between the braking surfaces displaced in the direction in which the thread moves while simultaneously being lifted off from the braking surface of the other braking body. Since with such a structure of the thread brake, the movable braking surface moves away from the thread in the direction of the movement of the thread, the thread will be subjected to a minor stress only when the braking is effected at a predetermined force. Furthermore, during the braking operation no displacements of the twist occur because the twisting path is by the thread brake limited to the range behind the thread brake. With the heretofore known thread brakes, the movable braking bodies are lifted off from each other further when thickened portions in the thread or knots pass between the braking bodies. Due to the fact that the braking bodies move further away from each other, the braking pressure is increased. Therefore, during the passage of the thread, the braking forces are subjected to certain variations.

In an effort to obtain a more uniform braking pressure on the thread which as a rule comprises knots and thickened portions, in connection with a thread brake on a spinning or twisting spindle whose thread passage is in the braking housing locally widened to form a pocket, the upper end face of which forms the stationary braking surface, there has been suggested a braking body cooperating with said braking surface and made of ferromagnetic material which braking body engages the stationary braking surface in view of the force of a magnet which is adjustable with regard to the braking surface and which at least partially extends around the thread passage.

The arrangement is such that the braking body which is displaceable by the thread is freely guided in the braking housing in such a way that the braking surface during the displacement will maintain its parallel location to stationary braking surfaces. The purpose of this arrangement consists in subjecting the respective thread to a substantially even braking force which with a thread having a uniform diameter will over the length of the entire braking surface with a thread having thickened portions or knots act only upon said thickened portions or knots while the loss at the braking surface in view of the increased braking pressure will be approximately compensated for at the knots or the thickened portions,

Experience has shown that the arrangement of braking bodies which are freely movable relative to each other while maintaining the parallel location of the braking surfaces will with some yarn numbers not yield the 0ptimum in uniformity of the braking pressure and of the thread tension.

It is, therefore, an object of the present invention to provide a thread brake which will more sensitively react to knots and thickened portions of the passing thread.

It is another object of this invention to provide a thread brake as set forth in the preceding paragraph which will be simple in construction and reliable in operation.

These and other objects and advantages of the invention will appear more clearly from the following specification, in connection with the accompanying drawings, in which:

FIGURE 1 represents a section through a thread brake provided in the hollow shank of a two-for-one twisting spindle.

FIGURE 2 is a perspective view of the threaded head removed from the brake housing of the thread brake and seen from below With the closure cover of the brake housing.

FIGURE 3 illustrates a perspective view of the threaded head of the thread brake as mounted on the brake housing.

FIGURE 4 represents a section through a further embodiment of a thread brake in the hollow shank of a twofor-one twisting spindle.

FIGURE 5 illustrates in section a third embodiment of a thread brake according to the invention arranged in the hollow shank of a two-for-one twisting spindle.

The thread brake according to the present invention is characterized primarily in that the stationary braking surface is unilaterally inclined and that the braking body is formed by a braking plate of ferromagnetic material which is adapted to cover the inlet opening in the thread passage into the pocket and which is pivotable in the direction of movement of the thread by the force of the passing thread. By means of the said pivotal movement of the brake body in the form of a braking plate, instead of a parallel movement, which braking body is pivoted against the variable force of the magnet acting upon the braking plate, it will be brought about that the braking force remains approximately constant so that the thread even when knots and thickened portions pass through the braking device will be treated very gently and thread breaks caused occasionally by a braking action of the thread brake will be safely avoided. The braking plate will be held about centrally with regard to the thread passage because the magnet has a plurality of poles and is axially magnetized and extends at least partially around the thread passage.

According to a further development of the invention, the outer marginal areas of the brake plate may be folded over away from the stationary braking surface toward the pocket, and at the side of the upper marginal area of the braking plate at the side wall of the pocket there may be provided a supporting mandrel extending below the braking plate. Such design and arrangement of the braking plate will, in view of the free movability and the rounded edges, bring about a great saving and gentle treatment of the thread. As a result of a supporting mandrel, the braking plate will when the influence of the magnet arranged thereabove decreases, not be able to pivot downwardly further than to the supporting mandrel extending below the braking plate so that the magnet will be able when advancing to pull back the braking plate to the unilaterally inclined braking surface,

According to a further embodiment of the invention, the braking plate may be connected centrally to the free end of a tilting lever which is pivotable about a pivot located above the entrance opening of the thread passage. In this way, also without a special supporting mandrel extending below the braking plate, the braking plate will always be safely held within the area of the braking surface so as to more or less strongly engage the braking surface in view of the variable magnetic force.

With a thread brake of the above design according to the present invention the tilting lever may be designed as a two-arm tilting lever, the free arm of which limits the magnitude of the tilting angle of the tilting lever by the latter engaging the braking housing and, if desired, may be accessible from the outside by a radial opening in the brake housing. In this way it will be possible that during the threading operation by means of a threading needle, the braking plate cannot move out of the range of the magnet to such an extent that it cannot be acted upon any longer by the magnet. For purposes of further simplifying the threading operation, the pivot may be arranged at the lower free end of a thread passage pipe which is displaceable downwardly against a spring pres sure so that during the downward displacement of the thread passage pipe until the free arm of the two-arm tilting lever engages the brake housing, if desired, at the edge of the radial opening in the brake housing, the braking plate will be lifted off from the stationary braking surface whereby the thread passage opening is freed so that a threading needle can be introduced from below.

In conformity with the present invention, the braking plate is, by the force of the thread passing through, tiltable in the thread moving direction against the force of the magnet. In order to make sure that the magnetic force of the magnet acting upon the braking plate substantially acts upon the lower area portion only of the braking plate, the magnet magnetizing the braking plate may in conformity with the invention be located unilaterally of the thread passage above the lower surface section of the stationary braking surface.

According to a further development of the present invention, the magnet magnetizing the braking plate may be secured against rotation and may be held by a threaded bushing which extends around the thread passage pipe forming the thread passage. The said threaded bushing is provided with an outer thread onto which a screw head is screwed which rests from above against the brake housing. By means of said screw head, it is therefore possible easily to determine from the outside the braking forces at which the braking plate is to engage the unilaterally inclined braking surface. T 0 this end, the screw head is turned in one or the other direction whereby the magnet, depending on the said direction of rotation is moved away or toward the stationary braking surface.

For purposes of improving the guiding of the magnet during its axial displacement, it is possible in conformity with a further development of the invention to provide a helical pressure spring between the magnet and the closure cover of the brake housing through which cover the thread passage pipe and the threaded bushing extend axially. In this way the axially directed movements of the magnet for adjusting the magnetic force acting upon the braking plate will be able precisely to follow the turning movements of the screw head.

For purposes of adjusting certain braking forces which act upon the braking plate and which are dependent on the turned position of the screw head with regard to the brake housing, the closure cover may have its upper side and the lower surface of the screw head resting thereupon be provided with locking noses or notches facing each other which will arrest the screw head in certain turned positions.

Advantageously, the individual positions of the screw head with regard to the brake housing may be indicated at the marginal area of the brake housing. To this end, in conformity with the present invention, the outer portion of the screw head may be marked by colors or notches indicating numbers or the like of which, depending on the rotary position of the screw head, a notch will be associated with a marker on the circumferential surface of the brake housing. Advantageously, the thread of the threaded bushing will with such a design of the thread brake have such a pitch that a rotation of the screw head by 360 will result in an axial movement of the threaded bushing and thereby an axial movement of the magnet to such an extent that all possibly necessary positions of the magnet with regard to the braking plate will be covered for obtaining different braking forces.

Referring now to the drawings in detail, the arrangement shown therein comprises a hollow shank 1 of the delivery bobbin carrier not further shown. The delivery sleeve 3 which tapers in upward direction and pertains to the delivery bobbin generally designated with the reference numeral 4 is in addition to other means held by a rubber ring 2 which is aranged over the hollow shank 1 in an annular groove 1a of a semi-circular cross section. The hollow shank 1 is provided with a spindle passage 5 which extends centrally through the hollow shank 1 of the delivery bobbin carrier. The thread 8 which is withdrawn from the delivery bobbin 4 and passes through the eye of the rotating arm 7, passes over the upper edge of the thread guiding pipe 6 downwardly through the passage 5.

According to the embodiments of FIGS. 1 and 4, the thread passing pipe 6 is centrally inserted into the cylindrical brake housing 9 and forms a part of the hollow shank 1. The lower end of the pipe 6 widens to a portion 10 which engages he inner walls of the brake housing 9 and rests on the bottom thereof while being prevented from rotating relative to the brake housing 9 by means of a pin or screw 39. The thread passage 11 of the pipe 6 widens locally within the section 10 so as to form a pocket 12 which starting at the bottom of the brake housing 9 conically leads downwardly into the spindle passage 5. The upper end face 13 of the pocket 12 is unilaterally inclined and serves as braking surface for the thread 8 which passes between said inclined surface 13 and an adjacent circular braking plate 14. The braking plate 14 under the influence of a multi-pole and axially magnetized magnet 15 is urged toward the upper end face 13 of the pocket 12 approximately centrally with regard to the thread passage 11. The said magnet is located in the brake housing 9 and extends around the thread passage 11. The end face 13 of the pocket 12 forms the stationary breaking surface and covers up the entrance opening of the thread passage 11 into pocket 12. In view of the force of the thread 8 passing through the passage 11, the brake plate 14 is tilted upwardly about its marginal area which above the entrance opening of the passage 11 engages the surface 13 serving as braking surface. In this way the thread 8 at the brake plate 14 moves along the shortest path which means it takes the path along the diameter line extending in the direction of movement of the thread.

When the multi-pole magnet 15 which extends around the thread passage 11 is arranged at the greatest possible distance from the braking surface 13 so that its magnetic flux no longer exerts any attracting effect upon the brake plate 14, the latter will tilt about its upper marginal portion into the position indicated by dot-dash lines in which it is engaged by the supporting spur 16 which at the side of the upper marginal portion of the brake plate 14 at the side wall 17 of the pocket 12 extends below the brake plate 14. In this position of the brake plate 14 it is made possible to effect a threading of the thread without being impeded by the circular plate 14. In order safely to hold the brake plate 14 on the supporting spur 16 and to avoid any sharp edges on the brake plate 14 for the thread passing thereover and to be braked, the outer edges of the brake plate 14 are folded inwardly from the braking surface 13 into the pocket 12.

The magnet 15, the bottom side of which is substantially parallel to the braking surface 13 is held by a threaded bushing 18 which has an outer thread and which extends around the pipe 6 with the thread passage 11, and is furthermore prevented from rotation by a pin 19 that is arranged on the inner wall of the brake housing 9 and extends into an axially extending longitudinal groove 20 of the magnet 15.

A screw head 22 is screwed onto the upper end of the threaded bushing 18 which together with the thread passage pipe 16 extends through the upper closure member 21 of the brake housing 9. The screw head 22 has its lower end face 23 resting on the cover 21 of the brake housing 9, whereas the uper end face of the screw head 22 through which end face the pipe 6 extends, serves as axial bearing for the hub 24 of the rotating arm 7. When the screw head 22 is turned, the threaded bushing 18 will, in conformity with the respective direction of rotation of the screw head 22, move either axially into said screw head or out of the same. The axial movements of the threaded bushing 18 are effected under the influence of the helical pressure spring 25 which in its turn rests on one hand on the bottom side of the cover 21 of brake housing 9 and on the other hand rests on the supporting shoulder 26 of the threaded bushing 18 to which the magnet 15 is connected.

In each of the three embodiments of FIGS. 1, 4 and 5, the pitch of the thread of the respective threaded bushing 18, and the pitch of the corresponding inner thread of the screw head 22 is such that a rotation of the screw head 22 by 360 brings about such as axial displacement of the bushing 18 and thereby of the multi-pole magnet 15 of FIG. 1 or the multi-pole magnet 27 of FIGS. 4 and 5 that for instance in the extreme position of zero degrees, the entire magnetic force of the magnet 15 will become effective to act upon the braking plate 14 or of the magnets 27 to act upon the braking plate 28. In the other extreme position of 360 the effective magnetic force will be rather weak in view of too great a distance between the magnet 15 and the braking plate 14 or the magnet 27 and the braking plate 28. Consequently, in its last mentioned position, the braking plate 14 according to FIG. 1 will tilt to the dot-dash position and will be caught and supported by the supporting spur 16, and the braking plate 22 of FIG. 4 which is stationarily held in the pocket 12 will merely tilt to the dot-dash line position.

In order to permit a better adjustment of certain braking values from the outside, the cover 21 of the braking house 9 as shown in FIG. 2 has its outer marginal area at its top side provided with a locking nose 29 having asociated therewith a plurality of locking notches 30 located in the lower end face 23 of the screw head 22. In this way the screw head 22 may be arrested in different rotated positions. For recognizing the various rotated positions of the screw heat 22 with regard to the brake housing 9 in an easier way, the screw head 22 has its lower marginal area 31 provided with markers 0r figures and according to FIG. 3 with notches 32 of which depending on the rotated position of the screw head 22 a notch 32 is associated with the arrow 33 on the outer circumferential surface of the brake housing 9.

The embodiments according to FIGS. 4 and 5, in contrast to the embodiment of FIG. 1 do not have a free circular brake plate 14 which is held merely by the magnet 15. Instead, according to FIGS. 4 and 5 the respective circular brake plate 28 is centrally connected to the free end of the two-arm lever 34 by means of a rivet 35 and is rotatable about the latter. The two-arm tilting lever 34 is tiltable about a pivot 36 which is located above the entrance opening of the thread passage 11 into the pocket 12. The free arm 37 of the two-arm tilting lever 34 extends through the radial opening 38 in the side wall 43 of an insert similar to section 10 of FIG. 1. The opening 38 has such a height that the two-arm lever 34 cannot be tilted further than to the dot-dash position in which the braking plate 28 is not influenced by the magnet 27 and the free arm 37 engages the marginal area of the opening 38. In this way an easy threading of the thread into the thread passage 11 to the passage 5 will be made possible by means of a threading needle, and both from the top as well as from the bottom. In order to be able more easily to introduce the threading needle from below, the passage 5 in the hollow shank 1 is curved below the pocket 12 in the direction of the braking surface 13. In view of this design of the passage 5 in cooperation with the steeply inclined stationary braking surface 13 the threading operation can be eifected without difficulties, and even better when the magnet 27 is displaced in the direction of the screw head 22 to such an extent that the braking plate 28 on pivot 36 tilts into the dot-dash line position which means that the attracting force of the magnet 27 is no longer effective.

Aside from the fact that in the embodiment of FIGS. 4 and 5 the mnlti-pole magnet 27 surrounds the thread passage 11 only partially and more specifically above the lower section of the unilaterally inclined braking surface 13, the arrangement of FIGS. 4 and 5 furthermore differs from that of FIG. 1 according to which the member 10 is secured in housing 9 against rotation by a screw 39 in that the member 40 is located eccentrically in the housing 9 with regard to the thread passage 11. In view of this design of the member 40, it is not necessary to prevent the member 40 from rotation by a screw. Furthermore, at the side of the magnet 27 there is sufficient space for an axial downward displacement of the magnet 27 to the bottom of the brake housing 9. It will also be noted that the brake surface 13 is inclined to a considerably greater extent than is the case with the embodiment of FIG. 1.

In this way, if desired, the magnet 27 may act more powerfully on the braking plate 28, as is the case with the embodiment of FIG. 1.

The third embodiment of FIG. 5 is very similar to that of FIG. 4, but differs therefrom in that it lacks a stationary pivot 36 arranged in the member 40 for the tiltable two-arm lever 34. The pivot 36 according to FIG. 5 is arranged at the lower free end of the thread passage pipe 6 which is adapted to be displaced downwardly against the force of the spring 41. Spring 41 rests on one hand on the upper end face of the thread bushing 18 and on the other hand rests on the annular supporting shoulder 42 which protrudes radially on all sides and 7 which has its other side resting against a supporting shoulder of the screw head 22. With this design of the thread brake the threading of the thread from ab ve and from below is particularly simple. It is merely necessary to displace the thread passage pipe 6 downwardly so that the circular braking plate 28 will in view of the engagement of the free arm 37 of the two-arm lever 34 tilt about the pivot 36 to the dot-dash line position whereby a rectilinear axial thread passage is freed. When the threading operation has been completed, in view of the thrust of spring 41, the thread passage pipe 6 is again moved to the position shown in the drawing in full lines, and the brake plate 28 can again under the influence of the magnet 27 approximately centrally with regard to the passage 11 engage th braking surface 13.

It is, of course, to be understood that the present invention is, by no means, limited to the particular showing in the drawings, but also comprises any modifications within the scope of the appended claims.

What we claim is:

1. A thread brake equipped textile spindle which comprises: a shank having a hollow portion forming the housing for said thread brake, conduit means axially extending from the outside of said shank through the latter and having a mouth leading into the interior of said housing for passing a thread through said conduit means into said housing, thread guiding member means located Within said housing near said mouth and having an inclined guiding surface for guiding a thread leaving said mouth, brake plate means of ferromagnetic material having a braking surface pivotable toward and away from said guiding surface for respectively exerting a braking force upon a thread passing over said guiding surface and facilitating the introduction of a thread into said hollow portion, and magnetic means likewise arranged Within said housing and movable selectively into and out of a magnetically effective distance from said brake plate means for respectively causing the latter to move to its thread braking position for exerting a braking effect on a thread passing over said guiding surface and out of said thread braking position for facilitating the introduction of a thread into said spindle.

2. A thread brake according to claim 1, in which said brake plate means has its marginal areas folded away from said inclined guiding surface.

3. A thread brake according to claim 1, which includes a member defining a chamber and being arranged in the lower portion of said housing while being connected to that portion of said conduit means which defines said mouth, said chamber defining member comprising stop means extending into said chamber, and said brake plate means being tiltable in said chamber from a thread engaging and braking position to a position in which it engages said stop means.

4. A thread brake according to claim 1, which includes lever means pivotally supported near the mouth of said conduit means and supporting the central portion of said said brake plate means.

5. A thread brake according to claim 4, in which said lever means has a first arm supporting said central portion of said brake plate means and also has a second arm for limiting the tilting movement of said brake plate means in a direction away from said guiding surface.

6. A thread brake according to claim 1, in which said conduit means is axially displaceable, and which includes lever means pivotally supported by the lower end of said axially displaceable conduit means and supporting said brake plate means.

7. A thread brake according to claim 1, in which said magnetic means is located unilaterally of said conduit means and above at least a portion of said inclined guiding surface.

8. A thread brake according to claim 1, which includes means for preventing said magnetic means from turning about the axis of said conduit means, and lever means operatively connected to said magnetic means for moving the same away from and toward said guiding surface in response to said screw means turning in one or the opposite direction.

9. A thread brake according to claim 8, which includes a closure member closing said housing, said conduit means and said screw means extending through said closure member, and pressure ring means interposed between said closure member and said magnetic means and urging the same away from each other.

10. A thread brake according to claim 9, in which said screw means includes a head member having a bottom surface resting on the top surface of said closure member, one of said last mentioned two surfaces being provided with nose means and the other one of said last mentioned two surface being provided with recess means for respectively receiving said nose means for selectively arresting said screw means relative to said closure member in a plurality of desired positions.

11. A thread brake according to claim 10, in which said head member and the outside of said brake housing are provided with indicating means for indicating the relative rotary position of said screw means relative to said brake housing.

References Cited UNITED STATES PATENTS 2,650,779 9/1953 Uhiig 5758.86 2,662,364 12/1953 Kingsbury 57-58.86 2,667,029 1/1954 Uhlig 5758.86 2,731,786 l/1956 Klein 5758.83 3,177,643 4/1965 De Halleux et a1. 5758.86

JOHN PETRAKES, Primary Examiner US. Cl. X.R. 57106; 242-149 

